# a = 10
# b = 3
# print(a+b)
# print(a-b)
# print(a*b)
# print(a/b)
# print(a%b)
# print(a//b)
# print(a**b)

# print(a > b)
# print(a < b)
# print(a == b)
# print(a != b)

# c = a + b
# print(c)
# a += b  # a = a + b
# print(a)
# a -= b
# print(a)

# a /= b
# print(a)

# a %= b
# print(a)

# a //= b
# print(a)

# a **= b
# print(a)

# print(10 > 2 and 20 < 2)  # F
# print(10 > 2 or 20 < 2)   # T
# print(not 10 > 2)         # F

a = None
print('a变量的内存地址是：{}'.format(id(a)))
print('None的内存地址是：{}'.format(id(None)))
print('True的内存地址是：{}'.format(id(True)))
print(a is None)	# 判断的是内存地址是否相同
print(a is True)
print(a is not True)
print(a is False)
